Electrical measuring instrument.



' f zlyfl 33 witw cooeo T. W. VARLEY. ELECTRICAL MEASURING INSTRUMENT. APPLICATION FILED MAR. 20, 1911.

Patented May 2, 1916.

UNITED strairas PATENT OFFICE.

THOMAS W. VARLEY, OF PITTSBURGH, PENNSYLVANIA, ASSIGNOR T0 WESTINGHOUSE ELECTRIC AND MANUFACTURING COMPANY, A CORPORATION OF PENNSYLVANIA.

ELECTRICAL MEASURING INSTRUMENT.

Specification of Letters Patent.

Patented May 2, 1916.

Application filed. March 20, 1911. Serial No. 615,553.

To all whom it may concern:

Be it known that I, THOMAS IV. VARLEY, a citizen of the United States, and a resident of Pittsburgh, in the county of Allegheny and State of Pennsylvania, have invented a new and-useful Improvement in Electrical Measuring Instruments, of which the following is a specification.

My invention relates to an improvement in electricalmeasuring instruments of that type wherein advantage is taken of a substantially constant magnetic field in combination with stationary and movable coils so disposed that a current passing through the stationary coil will shift or distort the lines of force of the magnet in such manner that they will cause a torque on the movable coil, the function of the stationary coil being simply to so shift the lines of force in the mag netic field and not necessarily to create the magnetic field itself, as in the ordinary electro-dynamometer; and the object of the invention is to provide a device of the character described having a high degree of accuracy in operation because of effective compensation for friction and in which there is substantially no liability to side thrust of the movable member because of the use of a double two-pole armature in a two-pole field, both the armatureand the field being provided with special windings.

In the following, I have described, with reference to the accompanying drawings, a structure illustrating one embodiment of my invention, together with certain inodifications of parts, the features thereof being more fully pointed out hereinafter in the claims.

In the drawings, Figure 1 is a front elevation, partly in section and partly diagrammatic, of a structure designed to be used as a watt hour meter. Fig. 2 is a transverse sectional view along the line AB of Fig.1. Fig. 3 is a perspectiveview showing the pole faces on one side of the magnet, other parts being removed or broken away. Fig. 4: is a diagrammatic view illustrating the connections. Fig. 5 is a detail view of the armature cup showing one form of winding. Fig.

6 illustrates a modification of the armature cup and Winding. Fig. 7 is a plan view of a mod1fication of the armature core,'and Fig. 8 is a diagrammatic view of a modification of the circuits of the device.

Similar numerals of reference indicate similar parts throughout the several views.

1 represents a substantially constant magnet here shown as a permanent horse-shoe magnet having pole -pieces 2 and 3 that are respectively provided with slots 4 and 5 to form polar faces 6 and 7, and 8 and 9.

10 indicates an auxiliary potential windng that is disposed around the polar faces in series-connected coils and is adapted to reversely magnetize the respective faces of each magnet pole piece.

11 indicates one of the load windings that is disposed around the two polar faces at one side in series connected coils, and 12 indicates the other load winding that is disposed around the two polar faces at the other side in series-connected coils, the respective load windings being adapted to reversely magnetize the pole faces around which they are disposed. The potential windings upon one magnet pole are also connected in opposition to the corresponding load windings.

13 is a support, preferably made of nonmagnetic material. and itself in turn sup ported in any convenient manner, not shown. Support 13 carries a tube 14, preferably of non-magnetic material, that serves to support a core 15 of magnetic material 16 is a screw in the bottom of tube 14 that constitutes a support for a shaft 17 having suitable bearings-only one of which is shownand carrying the armature cup 18; vertical or longitudinal adjustment of the armature with respect to the field poles being effected by means of the screw. Shaft 17 also carries the commutator member 19 to cooperate with brushes 20, 21, and a pinion 22 to drive any suitable indicating or registering mechanism (not shown).

' 23 indicates the armature Winding carried by armature cup 18, the winding and cup, together, constituting the movable element.

24, 24 indicate the generators here shown in duplicate, as the form of connection shown is that of a three-wiresystem.

25 indicates the load. 26 and 27 the mains and 28 the neutral'wire.

- 29 indicates the load shunt on one side of the system and 30 the loud shunt on the other side of the system.

31 indicates an adjustable resistance across the potential winding on one side of the magnetic circuit.

32 and 33 indicate adjustable resistances in the circuits of the load windings on the respective sides of the system. i

34 is an adjustable resistance in the potential circuit of the instrument, which includes the winding 23 of the armature cup 18, as the main potential winding, in addition to the winding 10.

The winding of the armature is illustrated more particularly in Figs. 5 and 6, both of which show a two-pole closed circuit winding. In Fig. 5, the winding is shown as extending downward vertically for approximately one half of the armature length, then circumferentially to a point diametrically opposite, then downward vertically the length of the remainder of the armature, then circumferentially on the same side of the armature, as before, to a point diametrically opposite, then upward vertically approximately one half of the armature length, then circumferentially' again on the same side of the armature to a point diametrically opposite, then vertically upward the length of the remainder of the armature, again circumferentially still on the same side of the armature back to the starting point, and so on, thus producing a double armature.

In Fig. 6, the winding of the armature is diagonally downward to a point diametrically opposite at the other end of the armature, thence circumferentially on the same side of the armature at a point diametrically opposite and at the same end of the armature, thence diagonally upward again on the same side of the armature to a point diametrically opposite to the point of beginning, and thence, still on the same side of the armature to the starting point, and

so on until the winding is completed. The armature winding is thus adapted to set up transverse magnetic fields that are reversed as to polarity near the opposite ends of the armature.

The o eration of the-apparatus is as follows: If no currents flow in the load windings 11 and 12, the currents in the armature winding, in conjunction with 'the undistorted lines of force of the constant field, produce substantially equal and opposing torques upon opposite ends of the armature,

and the armature, accordingly, remains sta tionary. However, when currents traverse the load windings 11 and 12, lines of force of the constant magnetic field are shifted so as to cause adjacent polar faces to be of unequal strength, and the opposing torques exerted upon the two ends of the armature are then no longer equal. A resultant torque is thus produced which causes rotation of the armature and which varies as the product of the current in the load windings and the potential current in the armature windings, or in proportion to the watts of the load.

As the auxiliary potential coils 10 upon one of the magnet poles are connected to oppose the corresponding load coils and upon the other pole to supplement the corres .)onding load coils, their arrangement is such that the torques produced by the currents therein, in conjunction with the currents in the armature winding, may oppose and neutralize each other. One of the functions of the auxiliary potential coils is to produce and maintain a difference of magneto motive force between the two faces of eachmagnet pole. In maintaining this magnetomotive force difference the number of turns in the auxiliary potential coils on one magnet pole may be so proportioned that they more than overcome the effects of the residual magnetism in that pole due to the load coils, and the auxiliary potential coils on the other magnet pole may be so proportioned that they assist the residual magnetism. However, the coils that more than overcome the residual magnetism may be of such number of turns as to neutralize the torque due to the residual magnetism. Thus it will be seen that the auxiliary coils may retard the armature to overcome the torque of the armature due to residual magnetism. \Vhile the auxiliary coils are primarily for the purpose of maintaining a difference of ma gnetomotive force and thus actually retard the armature an amount proportional to the torque due to the residual magnetism these coils may be utilized to give a slight resultant torque to the armature to overcome initial friction, this being done by causing the torques resulting from the use of the stationary potential coils, on opposite sides of the armature to be unbalanced. This resultant torque is, of course, proportional to the square of the potential. Another auxiliary resultant torque may also be exerted upon the armature to com ensate, either alone or in conjunction with the aforesaid means, for friction, this torque being caused by adjusting the armature longitudinally in order to vary the -relative positions of the movable and stationary windings. For instance, the

lower portion of the armature winding may be brought partially into the influence of tial.

The different windings of potential and load are arranged so as to neither add to nor decrease the total field of the constant magnet, so that the armature .cup rotates in a constant field regardless of the shifting effects, and, in consequence, the retarding torque varies as the speed, thewhole instrument acting as a watt hour meter.

By reason of the fact that the armature 18 of the two-pole type and the field 15 also two-pole, there is no tendency for s dethrust upon the shaft and bearings, which is an important advantage of the present meter.

To adjust for balance and to compensate for initial friction, the upper portion of the two parts of the core 15 maybe elliptically shaped, while the lower portion of the two parts of the core may also be in the shape of an ellipse of the same dimensions as the upper one but with its long axis at right angles to the .long aXis of the upper one, so that by turning the core, including both parts, any desired adjustment of the upper and lower air gaps relative to each other can be had. This is the equivalent of Iongitudinally adjusting the armature. A plan View of a core as thus constructed is shown in Fig. 7

Although, as shown, the load winding is placed on the magnet .poles and the main potential winding is on the armature, it should be understood that it may often be desirable to reverse the locations of these windings, in which case the auxiliary potential winding is preferably dispensed with and the requisite amount of potential current is sent through the load winding on the armature by any suitable arrangement of connections, as shown in Fig. 8.

It is obvious that the armature may be divided and one part balanced against the other, making virtually two armatures, although electrically, when connected in the same circuit, they would constitute but one.

I claim as my invention:

1; A wattmeter comprising a magnet having a substantially constant field, an armature Within said field, a winding upon each pole of the magnet adapted to produce different magnetizing effects opposite different end portions of the armature, and a winding for the armature adapted to produce reverse polarities at opposite ends thereof.

2. A. wattmeter comprising a magnet having a substantially constant field, an armature within said field, a winding upon each pole of the magnet adapted to produce different magnetizing effects opposite different end portions of the armature, and a Winding for the armature adapted to produce reverse polarities at opposite ends thereof, one of said windings being a load winding and the other a potential winding.

3. A wattmeter comprising a magnet having a substantially constant field,'an armature within said field, a winding upon each pole of the magnet adapted to produce different magnetizing effects opposite different end portions of the armature, and a winding for the armature adapted to produce reverse polarities at opposite ends thereof, and means associated with one of said windings and cooperating with the other to produce an auxiliary driving torque upon the movable member.

4. A wattmeter comprising a magnet having a substantially constant field, an arma- "ture Within said field, a Winding upon each pole of the magnet adapted toproduce different magnetizing effects opposite different end portions of the armature, and a Winding for thearmature adapted to produce reverse polarities at opposite ends thereof,'one of said windings being a load winding and the other a potential winding, and means associated with the load winding and cooperating with the potential winding to produce an auxiliary driving torque upon the movable member.

o. A wattmeter comprising a magnet hav.'

ing a substantially constant field, an armature Within said field, a. winding upon each pole of the magnet adapted to produce different magnetizing effects opposite different end portions of the armature, and a winding for the armature adapted to produce re-' verse polarities at opposite ends thereof, and means for adjusting the relative positions of the said windings.

6. A wattmeter comprising a magnet having a substantially constant field, an armature within said field, a winding upon each pole of the magnet adapted to produce different magnetizing effects opposite different end portions of the armature, and a winding for the armature adapted to produce reverse polarities at opposite ends thereof, and means for adjusting the armature longitudinally in order to vary the relative positions'of the said windings.

7. A wattmeter comprising a magnet having a substantially constant field, an armature within said field, a winding upon each pole of the magnet adapted to produce dii. tcrent magnetizing efl'ects oppnsii different end portions of the armature, and a winding for the armature adapted to produce reverse polarities at opposite ends thereof, and an auxiliary winding associated with one of the aforesaid windings and cooperating with the other to produce an auxiliary driving torque upon the movable member.

8. A wattn'ieter comprising a magnet having a substantially constant field, an armatnre within said field, a winding upon each pole of the magnet adapted to produce differentmagnetizing effects opposite differcut end portions of the armature, and a winding for the armature adapted to produce reverse polarities at opposite ends thereof, and an auxiliary winding associated with but partially opposing one of the aforesaid windings and cooperating with the other to produce an auxiliary driving torque upon the armature.

E). A wattmcter comprising a magnet having a substantially constant field, an armature within said field, a winding upon each pole of the magnet adapted to produce different magnetizing effects opposite different end portions of the armature, and a winding tor the armature adapted to produce reverse polarities at opposite ends thereof, an auxiliary winding associated with but partially opposing different portions of one of the aforesaid windings and cooperating with the other to produce an auxiliary driving torque upon the armature, and a shunt for the said auxiliary winding.

10. A wattmeter comprising a magnet having a substantially constant field, an armature within said field. a winding upon each pole of the magnet adapted to produce dili'erent magnetizing effects opposite different end portions of the armature, and a winding for the armature adapted to produce reverse polarities at opposite ends thereof. one of said windings being a load winding and the other a potential winding, and an auxiliary potential winding assoc ated with but partially opposing the load winding and coi peratingwith the other potential winding to produce an auxiliary driving torque upon the armature.

11. A wattmeter comprising a magnet having a substantially constant field, an armature within said field. awinding upon each pole of the magnet adapted to produce different magnetizing efi'ects opposite different end portions of the armature, and a winding for the armature adapted to produce reverse polarities at opposite ends thereof, one of said windings being a load winding and the other a potential Winding,

an auxiliary potential winding associated with the load winding but partially opposing diil'crent portions thereof and cooper-ab ing with the other potential winding to produce an auxiliary driving torque upon the armature. and a shunt for the said auxiliary winding.

'12. A wattmeter comprising a magnet having a substantially constant field, an armature within said field, a winding upon each pole of the magnet adapted to produce difi'erent magnetizing effects opposite different end portions of the armature, and a winding for the armature adapted to produce reverse polarities at opposite ends thereof, and an auxiliary winding associated with one of the aforesaid windings, and an adj ustaole shunt to the said auxiliary winding.

13. A wattmeter comprising a magnet having a substantially constant field, an armature withi said field. a winding upon each pole of the magnet adapted to produce different magnetizing efi'ects opposite different end portions of the armature, and. a winding for the armature adapted to produce reverse polarities at opposite ends thereof.

14. A meter comprising a magnet having a substantially constant field and two sets of opposite polar faces, and an armature rotatably mounted between the polar faces, the two sets of polar faces being respectively adjacent to different end portions of the armature.

15. A meter comprising a magnet having a substantially constant field, and two sets of opposite polar faces, an armature rotatably mounted between the polar faces, the two sets of polar faces being respectively adjacent to different end portions of the armature, and a winding upon each polar projec tion, those upon adjacent projections having opposite magnetizing effects.

16. A. meter comprising amagnet having a. substantially constant field, and an armature rotatably mounted between the poles of the magnet, each of said poles having two divisions that respectively oppose different end portions of the armature.

17. A meter comprising a magnet having a. substantially constant field, each pole of which has two divisions, a winding upon each polar division, an armature between the magnet poles having its end portions disposed respectively opposite different divisions of each magnet pole.

18. A meter comprising a magnet having a substantially constant field and two sets of opposing polar projections arranged axially side by side and an armature having a winding that produces reverse polarities at its opposite ends.

'19. Ameter comprising atwo-pole magnet having a substantially constant field and a pair of'pole faces foreach pole, and an armature having a double two pole winding.

20. A meter comprising a two-pole magnet having a substantially constant field and a pair of pole faces for'each pole, and an armature having a double two-pole winding, the polarities of the two portions of which .are reversed with respect to each other.

21. A meter comprising a two-pole magnet having a substantially constant field and a pair of pole faces for each pole, a winding for each polar portion thereof, andan armature having a double two-pole winding.

22. A meter comprising a twopole magnet having a substantially constant field and a pair of pole faces for each pole, and an armature having a double two-pole winding, the polarities of the two portions of which are reversed with respect to each other.

23. A meter comprising a permanent mag- 1 net having dividedpoles, a winding upon each polar division, and an armature, the divisions of each magnet pole being presented to different portions of the armature.

24. A meter comprising a magnet having a substantially constant field, windings respectively upon the different portions of each pole of the magnet, and an armature, the windings carried 'by portions of each magnet pole being opposite diiferent portions of the armature relative to its length.

25. In a wattmeter, the combination with a movable member, and means cooperating therewith whereby a main torque is exerted thereon approximately proportional to the product of potential and current, and also a supplementary torque that is approximately proportional to potential, of means also cooperating with the said movable memher for causing another auxiliary torque to be exerted upon the movable member ap proximately proportional to the square of potential.

26. In a wattmeter, the combination with a movable member, and means cooperating therewith whereby a main torque is exerted thereon approximately proportional to the product of potential and current, and also a supplementary torque that is approximately proportional to potential, of means also cooperating with the said movable member for causing an auxiliary retarding torque to be exerted upon the movable member approximately proportional to the square of potential.

27. In a wattmeter, the combination with a movable member, of 'means whereby a main torque is exerted thereon approximately proportional to tho product'of potential and current, and also an auxiliary retarding torque that is approximately proproportional to the square of potential.

28. In a wattmeter, the combination with a movable member, and means for cooperating therewith to produce a main torque substantially proportional to the product of potential and current, and also a supplementary torque that is substantially proportional to potential, of means also cooperating with the said movable member for causing an auxiliary retarding torque to be exerted that is substantially proportional to the square of potential, the said supplementary torque being substantially equal at a given current load to the retardation due to friction plus the said auxiliary opposing torque.

29. A meter comprising a two-pole magnet having a substantially constant field and a pair of pole faces for each pole, and means for maintaining a difference of magnetomotive force between the two pole faces of each pole of the magnet, and means for distorting said constant field.

30. A meter comprising a two-pole magnet having a substantially constant field and a pair of pole faces for each pole, means for maintaining a difference of magneto-motive force between the two pole faces of each pole of the magnet, and an armature having a double two-pole winding.

31. A meter comprising a two-pole magnet having a substantially constant field and a pair of pole faces for each pole, means for maintaining a difi erence of magneto-motive force between the two pole faces of each pole of the magnet, and an armature having a double two-pole winding the polarities of the two portions of which are reversed with respect to each other.

In testimony whereof, I have hereunto subscribed my name this 17th day of March,

THOMAS W. VARLEY. Witnesses:

OTTO S. SCHAIRER, B. B. Hmns. 

